Hello all,i recently start building a new gaming pc,i5-4460,sapphire r9 280 dual-x,hdd and one ssd.I did a stupid thing and bought a noname psu (this one http://www.e-shop.gr/deer-de146xd-550w-psu-p-PER.641607 with 2 years warranty) and now I am bumped cause I can't afford buying a new one.I don't intend to overclock,only will use all my cases fans(7 all of them),but I am worried about my wrong choice.A friend of mine gave me his cooler master 500w ps-500-psap-a3 (this one http://www.coolermaster.com/powersupply/extreme/extreme... ) .So my question is,which one should I use?Cause the noname has 80% efficiency and the Cm has 70%.and also the 12rail?i think the noname give more power to gpu,am I wrong?Thanks in advance!!!